diff --git a/toot/__init__.py b/toot/__init__.py
index 05e15ac..b3f3d1a 100644
--- a/toot/__init__.py
+++ b/toot/__init__.py
@@ -5,7 +5,7 @@ __version__ = '0.35.0'
 App = namedtuple('App', ['instance', 'base_url', 'client_id', 'client_secret'])
 User = namedtuple('User', ['instance', 'username', 'access_token'])
 
-DEFAULT_INSTANCE = 'mastodon.social'
+DEFAULT_INSTANCE = 'https://mastodon.social'
 
 CLIENT_NAME = 'toot - a Mastodon CLI client'
 CLIENT_WEBSITE = 'https://github.com/ihabunek/toot'
diff --git a/toot/api.py b/toot/api.py
index 3bb2c89..672849b 100644
--- a/toot/api.py
+++ b/toot/api.py
@@ -28,8 +28,8 @@ def _tag_action(app, user, tag_name, action):
     return http.post(app, user, url).json()
 
 
-def create_app(domain, scheme='https'):
-    url = f"{scheme}://{domain}/api/v1/apps"
+def create_app(base_url):
+    url = f"{base_url}/api/v1/apps"
 
     json = {
         'client_name': CLIENT_NAME,
@@ -504,6 +504,6 @@ def clear_notifications(app, user):
     http.post(app, user, '/api/v1/notifications/clear')
 
 
-def get_instance(domain, scheme="https"):
-    url = f"{scheme}://{domain}/api/v1/instance"
+def get_instance(base_url):
+    url = f"{base_url}/api/v1/instance"
     return http.anon_get(url).json()
diff --git a/toot/auth.py b/toot/auth.py
index 05b61b6..0ee2bac 100644
--- a/toot/auth.py
+++ b/toot/auth.py
@@ -9,21 +9,13 @@ from toot.exceptions import ApiError, ConsoleError
 from toot.output import print_out
 
 
-def register_app(domain, scheme='https'):
-    print_out("Looking up instance info...")
-    instance = api.get_instance(domain, scheme)
-
-    print_out("Found instance <blue>{}</blue> running Mastodon version <yellow>{}</yellow>".format(
-        instance['title'], instance['version']))
-
+def register_app(domain, base_url):
     try:
         print_out("Registering application...")
-        response = api.create_app(domain, scheme)
+        response = api.create_app(base_url)
     except ApiError:
         raise ConsoleError("Registration failed.")
 
-    base_url = scheme + '://' + domain
-
     app = App(domain, base_url, response['client_id'], response['client_secret'])
     config.save_app(app)
 
@@ -32,14 +24,30 @@ def register_app(domain, scheme='https'):
     return app
 
 
-def create_app_interactive(instance=None, scheme='https'):
-    if not instance:
-        print_out("Choose an instance [<green>{}</green>]: ".format(DEFAULT_INSTANCE), end="")
-        instance = input()
-        if not instance:
-            instance = DEFAULT_INSTANCE
+def create_app_interactive(base_url):
+    if not base_url:
+        print_out(f"Enter instance URL [<green>{DEFAULT_INSTANCE}</green>]: ", end="")
+        base_url = input()
+        if not base_url:
+            base_url = DEFAULT_INSTANCE
 
-    return config.load_app(instance) or register_app(instance, scheme)
+    domain = get_instance_domain(base_url)
+
+    return config.load_app(domain) or register_app(domain, base_url)
+
+
+def get_instance_domain(base_url):
+    print_out("Looking up instance info...")
+
+    instance = api.get_instance(base_url)
+
+    print_out(
+        f"Found instance <blue>{instance['title']}</blue> "
+        f"running Mastodon version <yellow>{instance['version']}</yellow>"
+    )
+
+    # NB: when updating to v2 instance endpoint, this field has been renamed to `domain`
+    return instance["uri"]
 
 
 def create_user(app, access_token):
diff --git a/toot/commands.py b/toot/commands.py
index e21f5b3..18e7be6 100644
--- a/toot/commands.py
+++ b/toot/commands.py
@@ -10,7 +10,7 @@ from toot.output import (print_out, print_instance, print_account, print_acct_li
                          print_search_results, print_timeline, print_notifications,
                          print_tag_list)
 from toot.tui.utils import parse_datetime
-from toot.utils import delete_tmp_status_file, editor_input, multiline_input, EOF_KEY
+from toot.utils import args_get_instance, delete_tmp_status_file, editor_input, multiline_input, EOF_KEY
 
 
 def get_timeline_generator(app, user, args):
@@ -305,7 +305,8 @@ def update_account(app, user, args):
 
 
 def login_cli(app, user, args):
-    app = create_app_interactive(instance=args.instance, scheme=args.scheme)
+    base_url = args_get_instance(args.instance, args.scheme)
+    app = create_app_interactive(base_url)
     login_interactive(app, args.email)
 
     print_out()
@@ -313,7 +314,8 @@ def login_cli(app, user, args):
 
 
 def login(app, user, args):
-    app = create_app_interactive(instance=args.instance, scheme=args.scheme)
+    base_url = args_get_instance(args.instance, args.scheme)
+    app = create_app_interactive(base_url)
     login_browser_interactive(app)
 
     print_out()
@@ -452,17 +454,19 @@ def whois(app, user, args):
 
 
 def instance(app, user, args):
-    name = args.instance or (app and app.instance)
-    if not name:
-        raise ConsoleError("Please specify instance name.")
+    default = app.base_url if app else None
+    base_url = args_get_instance(args.instance, args.scheme, default)
+
+    if not base_url:
+        raise ConsoleError("Please specify an instance.")
 
     try:
-        instance = api.get_instance(name, args.scheme)
+        instance = api.get_instance(base_url)
         print_instance(instance)
     except ApiError:
         raise ConsoleError(
-            "Instance not found at {}.\n"
-            "The given domain probably does not host a Mastodon instance.".format(name)
+            f"Instance not found at {base_url}.\n"
+            "The given domain probably does not host a Mastodon instance."
         )
 
 
diff --git a/toot/tui/app.py b/toot/tui/app.py
index b1d885a..330035b 100644
--- a/toot/tui/app.py
+++ b/toot/tui/app.py
@@ -336,7 +336,7 @@ class TUI(urwid.Frame):
         See: https://github.com/mastodon/mastodon/issues/19328
         """
         def _load_instance():
-            return api.get_instance(self.app.instance)
+            return api.get_instance(self.app.base_url)
 
         def _done(instance):
             if "max_toot_chars" in instance:
diff --git a/toot/utils/__init__.py b/toot/utils/__init__.py
index 8a39fd2..e8103ac 100644
--- a/toot/utils/__init__.py
+++ b/toot/utils/__init__.py
@@ -160,3 +160,29 @@ def _use_existing_tmp_file(tmp_path) -> bool:
 def drop_empty_values(data: Dict) -> Dict:
     """Remove keys whose values are null"""
     return {k: v for k, v in data.items() if v is not None}
+
+
+def args_get_instance(instance, scheme, default=None):
+    if not instance:
+        return default
+
+    if scheme == "http":
+        _warn_scheme_deprecated()
+
+    if instance.startswith("http"):
+        return instance.rstrip("/")
+    else:
+        return f"{scheme}://{instance}"
+
+
+def _warn_scheme_deprecated():
+    from toot.output import print_err
+
+    print_err("\n".join([
+        "--disable-https flag is deprecated and will be removed.",
+        "Please specify the instance as URL instead.",
+        "e.g. instead of writing:",
+        "  toot instance unsafehost.com --disable-https",
+        "instead write:",
+        "  toot instance http://unsafehost.com\n"
+    ]))